The biological attack using mail showed that letters can be contaminated as they move through the postal system and come in contact with contaminated letters, sorting equipment, delivery trucks, mail boxes and the postman""s mail bag. Decontamination in post offices does not do much to guard against subsequent recontamination before final delivery to an individual""s mail box.
According to the invention, mail is decontaminated in an individual""s mail box. When the mail box door is closed, the door is locked and a decontamination process is started, for instance by activating a UV light source producing UV and ozone. The door unlocks once the decontamination process has run for a prescribed time sufficient to destroy any biological organisms.
According to an aspect of the invention, the process can start after an adjustable delay after the door is closed and locked. Lamps can be activate to indicate process stages and errors. The process can be started manually if necessary by external switches. Interlock switches can detect that the door position to prevent the process from starting if the door is not fully closed or stop the process if the door is opened. A microcontroller can control the process.
Other aspects and features of the invention will be apparent from the following description.